The Smart & Brown collets are pretty similar in form to the W20 collets the Schaublin takes, although closer in size to the W25 size (some 102s came with those as standard, as well as some that had F23 - it's "complicated"). W25 are a bit longer and very slightly fatter than S&B, and have a metric (although oddball, 1.66 pitch) drawbar thread.
Great many similarities between your 102 and my Smart & Brown model L. I wonder if they use the same collets, mine are No. 2804
The Smart & Brown collets are pretty similar in form to the W20 collets the Schaublin takes, although closer in size to the W25 size (some 102s came with those as standard, as well as some that had F23 - it's "complicated"). W25 are a bit longer and very slightly fatter than S&B, and have a metric (although oddball, 1.66 pitch) drawbar thread.